North Korea claimed it successfully launched the rocket on April 5, carrying a satellite into orbit for the purpose of exploring space. But the North American Aerospace Defense Command (NORAD) said it had launched a missile whose top stages and payload landed in the Pacific Ocean. The U.N. Security Council condemned the launch yesterday, prompting North Korea's declaration today. Over the course of six years, the country has participated in talks (stalled since last year) with five countries — the U.S., China, South Korea, Japan and Russia. The negotiations have led the country to disable some of its main nuclear reactor and to disclose some of its weapons program in exchange for fuel and food.

"Now that the six-party talks have turned into a platform for infringing upon the sovereignty of the DPRK [Democratic People's Republic of Korea] and seeking to force the DPRK to disarm itself and bring down the system … the DPRK will never participate in the talks any longer nor will it be bound to any agreement of the six-party talks," North Korea's foreign ministry said today through the state-run Korean Central News Agency.

The Obama administration, which called on North Korea today to "cease its provocative threats," has previously said it wants to restart the talks.

The International Atomic Energy Agency said North Korean authorities had told its inspectors to leave the country and that the state had "decided to reactivate all facilities and go ahead with the reprocessing of spent fuel."

In its announcement today, the foreign ministry said it would "bolster its nuclear deterrent for self-defense in every way. It will take the measure for restoring to their original state the nuclear facilities which had been disabled under the agreement of the six-party talks and putting their operation on a normal track and fully reprocess the spent fuel rods churned out from the pilot atomic power plant."

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